From scraps to purification: innovative use of food waste-derived hydrochar in eradicating pharmaceutical pollutants

Environ Sci Pollut Res Int. 2024 May 17. doi: 10.1007/s11356-024-33630-1. Online ahead of print.

Abstract

Chemical products (CPs) such as carbamazepine and naproxen, present in aquatic environments, pose significant risks to both aquatic life and human health. This study investigated the use of hydrothermally carbonized food waste-derived hydrochar (AC-HTC) at three distinct temperatures (200, 250, and 300 °C) as an adsorbent to remove these CPs from water. Our research focused on the impact of hydrothermal carbonization temperature on hydrochar properties and the effects of chemical activation with phosphoric acid on adsorption capacity. Hydrothermal carbonization increased the hydrochar's surface area from 1.47 to 7.52 m2/g, which was further enhanced to 32.81 m2/g after activation with phosphoric acid. Batch adsorption experiments revealed that hydrochar produced at 250 °C (AC-HTC-250) demonstrated high adsorption capacities of 49.10 mg/g for carbamazepine and 14.35 mg/g for naproxen, outperforming several conventional adsorbents. Optimal adsorption occurred at pH 4, aligning well with the Langmuir and pseudo-first-order models. The hydrochar showed potential for regeneration and multiple uses, suggesting its applicability in sustainable wastewater treatment. Future research will explore scalability and effectiveness against a broader range of pollutants.

Keywords: Adsorption; Aquatic environment; Food waste-hydrochar; Hydrothermal carbonization; Wastewater treatment.